The invention concerns an apparatus for the production of transversely ribbed tubes, which has mold jaw halves which bear against each other along a common mold section with first and second front faces and form therebetween a mold passage, wherein each mold jaw half has vacuum passages which are in flow communication with the mold passage, and a cooling passage.
An apparatus of that kind is known for example from EP 0 065 729 A1. In that known apparatus the vacuum passages and the cooling passages open out on the same side of the mold jaw halves so that it is not possible reliably to prevent cooling fluid from passing into the vacuum passages. That can have an effect on operational reliability.
An apparatus for the production of transversely ribbed tubes with mold jaw halves provided with vacuum passages which are in flow communication with a mold passage of the mold jaw halves, the mold passage being formed along a mold section, is also known for example from DE 27 53 297 A1 or U.S. Pat. No 3,981,663.
DE 25 37 184 A1 discloses an apparatus for the production of transversely ribbed tubes, which has mold jaw halves which each have a cooling passage. The cooling passages of the mold jaw halves are in flow communication with cooling conduit loops in order to produce a desired cooling effect for the mold jaw halves.
The applicants' DE 195 17 023 C1 discloses an apparatus for the production of transversely ribbed tubes, having mold jaws which bear closely against each other with their front faces along a common mold section. In that known apparatus, along the common mold section, the mold jaws form at least two spaced-apart mold passages. Each mold passage communicates with associated vacuum passages, while the vacuum passages of adjacent mold passages in each mold jaw are in flow communication with each other through communicating passages. Valve devices in that arrangement serve to provide for a flow communication between the respective mold passage wanted, and a vacuum source.
The object of the present invention is to provide an apparatus of the kind discussed above, with which high-quality transversely ribbed tubes can be produced using structurally simple means, with a high level of productivity.